KARACHI: Snoring can damage your brain, Mail Online reported citing researchers. King’s College London scientists claim they’re the first to prove that sleep apnoea causes cognitive decline. Studies which have uncovered the same link in the past were never able to conclusively put two and two together. Any decline in brain power could affect memory as well as thinking skills, such as decision-making, reaction time and perception.

The condition causes breathing to stop and starts during the night, leading to loud snoring that can force sufferers to frequently wake up. The brain-hampering effects could be down to sleep apnoea cutting off blood flow and limiting oxygen levels, experts suggested. The researchers, working with colleagues from Germany and Australia, recruited 27 men, aged 35 to 70, who were newly diagnosed with mild to severe OSA but were otherwise healthy. Such patients are relatively rare as most OSA sufferers are also obese or suffer from conditions including diabetes, cardiovascular disease or depression.

These factors are why studies have never been able to tease out any causal proof, as these comorbidities themselves are risk factors for declining brainpower. The researchers also examined seven men, with similar health and education status, who did not suffer from OSA. For the study, participants wore electroencephalography skull caps while sleeping, which measured their brain waves. Their blood oxygen levels, heart rate, breathing and eye and leg movements were also tracked. Participants’ cognitive function was also tested.

The findings, published in the journal Frontiers in Sleep, show that those with severe OSA were less alert and had worse executive functioning, which includes being able to meet goals and stay focused. OSA sufferers also had worse short-term memory. And the milder their OSA was, the better they performed cognitively, according to the results. The researchers said that the mechanism behind their findings was unclear. But they suggested that it could be down to intermittent oxygen levels or changes in blood flow to the brain.

Lead author Dr Ivana Rosenzweig, who heads the Sleep and Brain Plasticity Centre at King’s College London, said: ‘We show poorer executive functioning and visuospatial memory and deficits in vigilance, sustained attention and psychomotor and impulse control in men with OSA. ‘This complex interplay is still poorly understood but it’s likely that these lead to widespread neuro-anatomical and structural changes in the brain and associated functional cognitive and emotional deficits.’ Whether comorbidities have similar negative effects on cognition above and beyond those caused directly by OSA is not yet clear.

‘However, our findings suggest that co-morbidities likely worsen and perpetuate any cognitive deficits caused directly by OSA itself.’ The condition, which affects around one in 10 over-30s, is caused by the walls of the throat relaxing and narrowing during sleep, which interrupts normal breathing. Those with the condition tend to suffer from loud snoring, gasping, snorting or choking noises during sleep and wake up a lot.